Crystal nucleation rates for particles experiencing short-range attractions: Applications to proteins

A kinetic model for the nucleation of a crystalline phase consisting of par ticles experiencing short-range attractions is developed, Of particular sig nificance is the proximity of the metastable fluid/fluid phase boundary. Th e model incorporates self-consistent thermodynamics, changes in gradient di ffusivity, and density fluctuations in the vicinity of the critical point. Density fluctuations associated with the spinodal of this metastable phase transition greatly enhance nucleation rates, suggesting that experimental c onditions may be found where rapid nucleation and slow crystal growth can b e achieved by moving the metastable critical point relative to the solubili ty boundary. (C) 2000 Academic Press.